I actually built a couple of "micro-cabin" prototypes that I was going to place on some land I have in Colorado near a couple of trail heads. They were basical

I actually built a couple of "micro-cabin" prototypes that I was going to place on some land I have in Colorado near a couple of trail heads. They were basically solar powered bunk-beds. Each "room" was 48"h x 54"w x 96"l, had a 36" "porch" and would have a locking door that used 4G to reset the code on check-in, a window, a mini heater, a foam mattress and a shelf. I never made it past building the prototype in my garage, but I've always loved the idea.